mr. obama came to the president in the midst of a global financial crisis and two wars. he has had to reshape america's role in the world, the boldness of his accomplishments-- health care reform-- has been divisive. in his first inaugural speech president obama promised a new vision for a troubled country. >> today i say to you that the challenges we face are real they are serious and they are many. they will not be met easily or in a short span of time but know this, america, they will be met! (cheers and applause) >> rose: four years later much work remains on major issues from climate change to immigration reform to the debate about taxes and spending and the most recent focus on gun control joining me to assess barack obama is a group of distinguished scholars and historians. from boston, dorr wince kearns goodwin, she won the pulitzer prize for her book called "no ordinary time." her latest biography "team of rivals" formed the basis for steven spielberg's movie "lincoln." she'll join us later. from nashville, jon meacham, he won a pulitzer prize for the biography